This book is an excellent review of gauge fields. The scope is from Maxwell to renormalization groups, with an epilogue that diagrammatically sums up the last few chapters. The book is a popularization, not a text book. It is comparable to Zee's "Fearful Symmetry". If you don't know what gauge fields, QED and QCD are about, this is probably not the place to start. But if you'd like a very readable overview, with equations, but without problems, I recommend this one highly.